1.Technical Field
Aspects of the present invention relate to an inductor formed such that a core on which a coil is wound is accommodated in a case.
2.Related Art
Conventionally, an inductor is used as a reactor in an electric circuit. An example of such an inductor (reactor) is disclosed in International Publication No. WO 2007/108201 (hereinafter, referred to as '201 publication).
FIG. 7 is a perspective view showing a configuration of a conventional reactor disclosed in '201 publication. The reactor 101 is configured such that a core 120, which is O-shaped when viewed from directly above, and a pair of coils 130, which are wound around the core 120, are accommodated in a case 110.
A fixing member 140 is used to retain the core 120 in the case 110. FIG. 8 is a perspective view showing the fixing member 140 of the conventional reactor. As shown in FIG. 8, the fixing member 140 is made by bending a metal plate (e.g., a stainless-steel plate) into an L-shape at a corner portion 143. In addition, an opening 145 is formed at a position in the vicinity of one of corners (upper left corner in FIG. 8) of an upper plate 141, which extends from the corner portion 143 in an horizontal direction, in order to fix the fixing member 140 to the case 110 with a bolt 152 inserted through the opening 145 (FIG. 7).
A side plate 142, which extends from the corner portion 143 in an vertical direction, is bended into a U-shape in the middle thereof. The second portion 142 is inserted into a space between an inner surface of a side wall 111, which is one of side walls of the case 110, and the core 120. Thus, the side plate 142 biases the core 120 toward a side wall (not shown in FIG. 7) opposed to the side wall 111.
Furthermore, a slit 144 is formed in the middle of the upper plate 141 of the fixing member 140 (FIG. 8) to divide the upper plate 141 into two parts. One part has the opening 145 as described above, and the other part of which a fore-end portion is bent downwardly and a leaf spring 141a is formed. In a state where the fixing member 140 is fixed to the case 110, a fore-end of the leaf spring 141a elastically push-contacts a top surface of the core 120 and biases the core 120 toward a bottom surface of the case 110.
As described above, the fixing member 140 retains the core 120 in case 110 by biasing the core 120 toward the side wall and the bottom surface of case 110.
However, in the conventional reactor 101, since the core 120 is biased toward the bottom surface of the case 110 with an elasticity produced by the leaf spring 141a itself, a stress concentration is likely to occur on the upper plate 141 of the fixing member 140, in particular, at the end of the slit 144. Therefore, there remain problems that the fixing member 140 may be broken by an excessive stress given to the upper plate 141 due to a big impact load.